Bail wat signaling system



(No Model.) 3 Sheets-Sheet; 1. M; OORRINGTON.

RAILWAY SIGNALING SYSTEM.

Patented Nov. 6

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(No Model.)

No. 528,593. Patented Nov. 6,-1894.

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Patented Nov. 6

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MURRAY CORRINGTON, OF NEW YORK, N. Y.

- RAILWAY SIGNALING SYSTEM.

SPECIFICATION forming part of Letters PatentNo. 528,593, dated November6, 1894.

Application filed December 3, 1891, Renewed July 14, 1894. Serial No.517.612. (NomodeL) block system, the essential feature of whichconsistsin the arbitrary division of the line of a railway into a series ofsuccessive sections, of convenientlength, according to the necessitiesof the traffic, at the entrance to and exit from which sections,signaling points are established, such sections being technically termedblocks. principle governing the operation of such a block system is thatall trains passing in succession in the same direction along the railwayshall be so controlled or directed by the indications of the signalsexhibited at or near the entrance to each block, that only a singletrain, ora determinate number of successive trains, as the case may be,shall be permitted to be within the limits of any one section at thesame time. When only a single train is permitted within a section, thesystem is known as an absolute block system) When two or more trains arepermitted tobe within the same section at the same time, the system isknown as the permissive block system. Ordinarily, in a block system, atrain on entering a section causes a signal to be exhibited at or nearthe entrance thereof, which indicates its presence within that section,an operation which is termed setting the danger signal. When the trainin question passes out of the opposite end of the section, it reversesthe danger signal at the entrance, causing the same automatically toreturn to its normal position, which is termed returning the signal tosafety. In practice, however, it may frequently happen that it is notdesirable to reverse a given danger signal at the entrance of a section,until the train which caused it to be exhibited has passed through two,three, or even more succeeding sections. In such case the organizationwhereby this plan is carried into effect is known as an overlappedsystem. r

The fundamental My invention embraces all the essential featurescharacteristic of each of these three systems, 1 6., the absolute block,the permissive block and the overlapped system, and is capableof beingutilized in connection with, or applied to either, without modification,other than the addition of an independent conducting wire for eachadditional overlapped block section of a series.

My apparatus may be employed as an absolute block for one class oftrains, as for instance, passenger trains, and as a permissive block forother classes of trains, as freight or merchandise trains.

When operated under normal conditions my apparatus is automatic in itsaction, but it is nevertheless capable of being operated manually, whenrequired.

In the accompanying drawings I have shown one organization of apparatussuitable for carrying my invention into effect.

In the drawings, Figure 1 is an elevation partly in section, of asignaling, apparatus embodying myinvention. Fig. 2 is a side elevationof a signal, signal-post and track-instrument. Fig. 3 is a frontelevation of a portion of a track-instrument. Fig. 4 is a detailview,'o'n an enlarged scale, of the apparatus for releasing or reversinga distant signal, and Fig. 5 is a diagram exemplifying the mode ofoperation of a series of signals according to my invention.

The signal, signal-post and track-instrument illustrated in Figs. 2 and3, and'more in detail in Figs. 1 and 4, is placed in a conspicuousposition at or near the entrance of each block or section, at such aheight as to be in plain sight of the engine-driver of an approachingtrain, when about to enter upon the block.

The complete apparatus consists of six principal parts, viz: the visualor other indicator for absolute block the visual indicator forpermissive block; the track-instrument;

the mechanism for controlling and effecting the indications of therespective indicators; the apparatus for reversing one signal by theoperation of exhibiting another, or as a sequence of such operation, andthe electric illuminator for lighting the visual indicators during theperiod of occupancy of the block by a train.

In the drawings,A represents a case or box, preferably having a circularface, which is affixed to the top of a suitable post or standard Bextending upward from a hollow pedestal B which is firmly fixed upon asuitable foundation near the line of the track. The standard B islikewise hollow, to permit the passage of a rod b, which has a verticalmovement within it, and 'rests loosely upon the outer end of a rigidlever D, which is mounted upon a fulcrum d in a position preferably atright-angles to the track. To the opposite end of the lever D isattached a treadle E, consisting of a rigid bar, lying parallel to andalongside of one of the rails F of the track, one of its ends beingpivoted to the rail, or in a fixed relation thereto, as shown at 6,while the other end is normally raised a little above the top of therail, as seen at c.

It will be understood, without further detailed explanation, that theweight or impact of each successive wheel of a passing train, willdepress the treadle E to the level of the top of the rail, and thereforetend to raise the rod 12 vertically through a corresponding distance.The lever D and treadle E return to their normal position after thepassage of each wheel of the train, by reason of the recoil of thespring D, but the vertical rod b, not being fastened in any way to thelever D, tends to return by the action of gravity alone.

I remark that the lever E is not an essential feature of my invention,since it is obvious that the end of the lever D itself may be placed insuch proximity to the rail as to be depressed by the direct impact ofthe wheels of the passing train, but I prefer to employ the lever E inthe manner shown in the drawings, in order to avoid the sudden blows andshocks with which the wheels would otherwise strike against the end ofthe lever D.

In order to carry out the mode of operation contemplated in myinvention,l apply tothe rod b a suitable retarding device, which,although not in the least interfering with the free upward motion ofsaid rod, acts to delay its return, under the action of gravity, to itsnormal position. Various retarding devices may be applied to efiect thispurpose, such devices being well-known in the art to which my inventionrelates. I prefer to use, and have shown in the drawings, a piston 0moving air-tight, or nearly so, in a cylindrical chamber formed withinthe pedestal of the standard B. WV hen the piston O is forced upward,air may be freely admitted beneath it by means of a valve; but theegress of the air, to permit the gradual descent of the piston may bemade to take place through a small opening and may be easily regulatedto cocupy any length of time required for the longest train to pass agiven point. As the particular form of retarding device used is whollyimmaterial, so far as relates to the subject-matter of my invention, amore detailed description of this portion of the apparatus is deemedunnecessary.

Upon the face of the case or box A I place a visual signal, capable ofgiving two or more distinct indications of different signification; thenumber of such distinct indications being equal to the maximum number oftrains which are to be permitted to occupy the cor responding blocksection at one and the same time. The form and construction of this visual signal may be varied. I usually prefer, for the sake of simplicity,to construct-it as shown in Fig. 2,in the shape of a large circulardial,

divided into the required number of equal spaces, and provided with aconspicuous movable index a, capable of pointing to either one of thenumbered spaces,but if preferred, a semaphore arm, or groupof arms mightbe moved in the same way to give correspond- 8 ing indications, readilydistinguishable from one another. The particular dial shown in thedrawings is designed to give three such distinct indications, and thusmay serve to give information of the presence, in the coro respondingblock, of a number of trains not exceeding three.

In the form of indicator shown, the normal position of the index a whenno trains are on the section, is at zero, as shown in Fig. 2. 5

Each successive train, entering the section, causes the index to advanceone division while each train passing out of the section, in likemanner, causesit to retrograde one division, so that the position of theindex at all I00 index a are a toothed wheel Gand apinion g.

The teeth of this pinion engage with another toothed wheel H, upon theaxis of which is fixed a pinion fitted with movable pivoted pawls h h itinstead of rigid teeth. Ashouldered projection 11' fixed upon the upperend I 10 of the rod b, engages with one of these pawls whenever the roddescends, and thus causes the wheels H and pinion g to turn through adeterminate distance, but whenever the rod is raised the projection 19pushes the pawl aside, and passes by it without imparting movement tothe axis upon which it is fixed.

In constructing the apparatus forpractical operation, it may be founddesirable to omit one of these pawls, to the end that in case [20 thereleasing mechanism should become accidentally disarranged, and notperform its function, and thus fail to indicate the exitof a train ortrains from the section, the rod B will nevertheless be permitted todescend, :2

after the prescribed number of trains has entered the section, and thusthe risk of the dial mechanism being turned forward until it is brokenwill be avoided. The wheel G engages with a pinion 11 upon the axis ofwhich is a wheel I, having a detent J upon its periphery, adaptedtoengage with a shoulder formed upon the end of a pivoted lever K whichlever is movable in one direction by the attractive force of anelectromagnet M, and in the other by a retracting spring k. A coiledspring N is affixed to the axis of the index a, the office of which isto effect the retrograde movement of said index in the mannerhereinafter explained.

The release or reversal of the action of the signal, or in other words,the production of the retrograde movement of the index a, is preferablyeffected through the agency of electricity. As it is very desirable thatsuch release or reversal, in the case of any given signal, should in nocasetake place until the train leaving the section shall have passedcompletelyunder the protection of the signal at the entrance of the nextsection in the series, I have provided that the releasingim pulseshallonly be transmitted afterthe entire train has passed the signalingpoint. The apparatus by which this is effected is best seen in Fig. 4. Sis aswitch or contact-lever made in two parts 8 and s and hinged at itscenter (where it is pivoted to the standard 16,) in such a manner thatwhen the enlargement b of the rod b passes upward, it pushes the rolleraside, the spring t yielding to the pressure, and produces no effect,but when it passes downward (the hinged joint being now rigid,) thespring t yields, and the end 8' of the lever S is brought into contactwith the plate 0, completing the circuit of the .wires l and 2, andtransmitting an electrical impulse back to efiect the retrogrademovement of the signal at the entrance of the preceding section. It willbe understood, therefore, that it is not possible to change theindication of any signal, in respect to the number of trains which haveenteredthe corresponding block section, nor to reverse or alter theindication of the preceding signal, until the entire train has passedany given signaling point. The rod bis raised by the impact of the firstwheel of the train,

and the retarding device hereinbefore re-" ferred to acts to prevent itsreturn far enough to operate the mechanism of the signal, before it israised again by another wheel of the train. This action is repeateduntil every wheel in the train has passed, after which the rod slowlydescends, and actuates the signal,

as well as the reversing apparatus of the signal last passed, ashereinbefore explained. If for any reason, it should be deemedpreferable, that the preceding signal in the series should be releasedor reversed at the instant that the first wheels of the train pass outof the block section, it will be evident that this may be accomplishedby inverting the position of the lever S, or in other words, turning itupside down, and thus effecting the electric contact during the upwardinstead of the downward movement of the projection b upon the rod B. v

The apparatus thus far described constitutes a permissive block system,by which an engineer on arriving at the entrance of a may also make useof an additional signaling device. An electric conductor 7, carrying aconstantcurrent, divides at 6 into two branches 5 and 4, anelectro-magnetic coil B being included in the former branch, which maybe availed of to operate any well-known form of alarm. or'visual signal.The branches 4 and 5 terminate in contact-points q and 1", between whichplays a contact-arm P, connected with the circuit-wire 3. A cam n isfixed upon the axis of the index a, in such position that it willmaintain the contact-arm P in contact with stop q, whenever the indexstands at zero, and thus divert the current from the branch 5 containingthe coil R, but which in any other position of the index a, will permitthe,

arm to touch the stop 4", thus bringingthe coil B into the circuit. Anywell-known form of visual, audible or other signal whatsoever may beactuated by the coil R, either by direct or by inductive or otherindirect action. An illuminating device L, which may be an ordinaryincandescent electric lamp,is placed in the same branch of the circuitwith the coil R, and will in such case necessarily continue to belighted so long as any trains whatever are on the section guarded by it.Hence it will be understood that the lamp L, when taken by itself,constitutes an absolute signal, and at the same time serves to renderplainly visible at night the indications of the dial-and index whichconstitute the permissive signal.

In case the engine-driver of a train having orders to run under theabsolute system should fail to see, or from any other cause shoulddisobey the danger signal and enter upon an occupied block, such signalat the entrance of that block cannot be reversed nor returned tosafety,by reason of the exit of a preceding train from the block, and soexhibit an erroneous signal to a succeeding train, and permit it toenter the occupied section with the understanding that such section isclear, while as a matter of fact the second train is stilloccupying it;but, on the contrary, the arrangement of the mechanism is such that thesystem will in such case at once convert itself into a permissive block,for the protection of the train which has disobeyed the signal, as wellas for the proper information of the train which follows it. So, also,if trains are runningunder permissive orders, allowing, for instance,four trains within a section at the same time, and a fifth train shouldenter wrongly, the system at once becomes an extended permissive system,for the protection of this train, and the proper information of thefollowing ones.

, It is an. invariable characteristic of the operation of the wholesystem, whether trains be running under absolute or permissive orders,that the signal at the entrance of a section can in no case be returnedto safety, so long as any train whatever remains within that section.

I provide for the manual control of the signals, in case of accident oremergency, by means of the hand-switches shown in Figs. 1 and 4.. Theswitch w serves to interrupt the circuit and to thus prevent thetransmission of a releasing or reversing impulse back to the lastsignaling point, while the switch y, on the other hand, may be employedfor the purpose of transmitting such reversing or releasing impulse, byclosing the circuit as required.

The theoretical diagram, Fig. 5, serves to show the relation of theseveral signals of a series to each other, the trains being assumed topass along the track F F in the direction indicated by the arrow. Thecurrent for actuating a whole series of signals may be supplied from asingle common generator or source of electricity as shown at Z, whichmay be either a dynamo-electric machine as indicated in the drawings, ora battery of suflicient capacity, or it may be supplied from a localbattery or dynamo at each station. One terminal of the main generator Zmay be put to earth, as shown in the figure, or a return wire may besubstituted for the earth in a manner well understood among thoseskilled in the art. The current from this generator flows constantlythrough each apparatus of the series, as indicated by the arrows, beingdiverted to and from any one of the block signals as hereinbeforeexplained, without necessarily interrupting its flow. The impulsesrequired for releasing or reversing the signals may by preference bederived from the same circuit, though a separate generator may be usedif desirable with equally effective results.

The dotted lines in Fig. 5 indicate the manner in which the circuits maybe connected so as to efiect the overlapping of the blocks, which issometimes deemed advantageous in practice. The releasing impulse, insuch case, is transmitted, not from the next succeeding signaling point,but from the second, third, or any other, as required. The operation insuch case will be readily understood by the aid of the drawings withoutfurther explanation.

The construction of the various parts of my apparatus may be widelyvaried without departing from the spirit of the invention.

I claim as my invention:-

1. In a railway signaling system, the combination, substantially as setforth, of a visual signal consisting of an index capable of moving byadvance or by retrograde movements over successive intervals of a spaceddial: mechanism whereby an advance movement of said index over one spaceof said dial is automatically imparted by the passage of each of one ormore trains beyond a signaling point at the entrance of a signalsection; retracting mechanism, which by its recoil, constantly tends toimpart to said index a retrograde movement over said dial; and anescapement automatically released by the passage of each of one or moretrains beyond a signaling point at the exit of said signal section;which escapement, whenever actuated, permits said index to retrogradeover one interval of said spaced dial.

2. In a railway signaling system, the combination, substantially as setforth, of a treadle actuated by the impact of a moving train; a rodwhich is raised by a connection with said treadle, but is restored toits normal position by the action of an independent retracting device, aretarding device capable of acting upon said rod only during its returnmovement, a visual index capable of moving by advance or by retrogrademovements over successive intervals of a spaced dial; and mechanismwhereby an advance movement of said index over one space of said dial isimparted by each return movement of said raised rod.

3. In a railway signaling system, the combination, substantially as setforth, of a spaced dial, avisual index capable of moving by advance orby retrograde steps over the intervals of said dial; a rod deriving itsmotion from the impact of a moving train, whereby successive advancemovements are imparted to said index; a spring which is wound by theadvance movement of said index; a detent which acts to prevent therecoil of said spring, and a device actuated from a distant signalingpoint, whereby said detent may be withdrawn to permit a retrogrademovement to be imparted to the index by the recoil of said spring.

4. In a railway signaling system, the combination, substantially assetforth, of aspaced dial; a visual index capable of moving by advanceor by retrograde steps over the inter- Vale of said dial; a rod derivingits motion from the impact of a moving train, whereby successive advancemovements are imparted to said index; a spring which is wound by theadvance movement of said index, a de tent which acts to prevent therecoil of said spring; an electro-magnet, included in a circuitextending from a distant signaling point; and a circuit-closer foractuating said electromagnet and withdrawing said detent, the action ofwhich is controlled bythe retrograde movement of the visual signalingapparatus at said distant signaling point.

5. In a railway signaling system, the combination, substantially assetforth,of a spaced dial; a visual index capable of moving by advance orby retrograde steps over the intervals of said dial; an electriccontact-switch, which is held in one position by the index of said dialwhen at its zero point, but in another position at all other points inthe revolution of said index, an electrically actuated signal, includedin a branch of a normally closed electric circuit, which branch iscutout when said index and contact switch are in the normal or zeroposition, but which is included in said electric circuit when said indexand switch are out of the normal position.v

6. In a railway signaling system, the combination, substantially as setforth, of a sig nal comprising a spaced dial and a visual index movingby advance or by retrograde steps over theintervals of said dial; anelectric contact-switch, which is held in one position when the index ofsaid dial is at its zero point, but in another position at all otherelectric current whenever said switch is in any other than the normal orzero position, whereby said visual signal is illuminated whenever itsindex is out of the position of zero.

7. In a railway signaling system, the combination, substantially as setforth, of a rod deriving a longitudinal motion from the impact of amoving train, a shoulder or angular projection upon said rod, and awheel provided with a succession of hinged pawls upon its periphery,which engage with said shoulder when the rod is moving in one directionbut not when it is moving in the opposite direction, -and a visual indexmoved by said wheel.

8. In a railway signaling system, the combination of an electric switch,shifting apparatus for operating .said switch to make or break a.circuit, a signal operating circuit opened or closed by said switch, anda train actuated mechanism for mechanically imparting a determinateadvance movement successively to said shifting apparatus by theautomatic action of each of one or more trains in passing beyond asignaling point.

9. In a railway signaling system, the combination of a spaced dial, apointer moving over the same, and a train actuated mechanism formechanically imparting to said pointer a determinate advance movementsuccessively by the automatic action ofeach of one or more trains inpassing beyond a sign'aling point.

In testimony whereof I have hereunto subscribed my name this 28th day ofNovember,

MURRAY CORRINGTON.

Witnesses:

EDWARD H. ROGERS, CAROLINE E. DAVIDSON.

